In order to prevent consumers from suffering serious or even fatal injuries caused by electrical shock, manufacturers of electrical cords, such as cord sets and power supply cords, have sought to caution consumers of the various dangers that exist when electrical cords are not used properly. Electrical cord sets are particularly susceptible to causing injury or death due to electrical shock. For example, if a male end of a cord set is inserted into a power source, a dangerous situation exists unless a female end of the cord set is also appropriately connected, for example, to a power supply cord which is hard-wired into a device, such as, for example, a computer.
Historically, manufacturers typically warned consumers of many of the various hazards caused by improper use of electrical cords on the outer or prime packaging of the electrical cord or associated product. Unfortunately, the warnings included with the packaging were largely unsuccessful in increasing safety because consumers ordinarily discard the packaging prior to initial use of the electrical cord. As such, any communications provided with the packaging were ill-suited for reminding consumers of potential dangers upon subsequent use. The problem was exacerbated when the communications were provided on an inside surface of the packaging because the warnings often would go entirely unnoticed by the consumer.
As a result of the inadequacy of warnings provided with packaging, manufacturers have been increasingly turning to approaches in which a long-term source of cautionary information (regarding electrical cord safety) is permanently affixed to the electrical cord. However, because electrical cords generally have outer insulation jackets that are composed of materials which have a relatively low surface energy (such as various rubbers and thermoplastics), securely attaching the source of the cautionary information has proven to be difficult. In addition, because of the significant "wear and tear" that is typically associated with the use of electrical cords, Underwriters Laboratories Incorporated ("UL") has adopted Standard 817 for Safety of Cord Sets and Power Supply Cords.
In order to obtain UL approval pursuant to Standard 817, the source of the cautionary information, which is attached to the electrical cord (usually within 12 inches of at least one of the ends), must be able to withstand exposure to harsh conditions, such as, heat, humidity, water immersion, freezing temperatures, pulling or snagging, ultraviolet light, and other conditions. Following exposure to such severe conditions, UL 817 requires that the source of cautionary information must be able to hold a 5 lb. (.apprxeq.2.286 kg) weight without slipping from an original position on the cord by more than 0.5 inches (.apprxeq.1.28 cm), nor should the source for cautionary information crack by more than 0.06 inches (.apprxeq.0.16 cm).
By way of example, U.S. Pat. No. 5,658,648 describes adhesive labels that have passed tests which suggest that they are able to withstand long-term "wear and tear" when used as a source for cautionary information when applied to elongated objects, such as electrical cords. In fact, the adhesive labels described in U.S. Pat. No. 5,658,648 have satisfied the requirements necessary for UL 817 approval.
However, the use of adhesive labels as the source of cautionary information has not been fully satisfactory for all electrical cord applications. In particular, some electrical cords are designed specifically for certain applications in which durability is especially important, such as electrical cords designed for outdoor use or specially designed oil-resistant electrical cords (e.g., cords resistant to hydraulic oil, motor oil, fuel oil, and the like). With respect to the latter, some electrical cords are provided with special oil-resistant insulation jackets, which are identified in the art by including the letter "o" in acronyms that are known customarily in the art (e.g., "SJOW-A" refers to an oil-resistant cord, while cords identified as "SJW-A" are not specially designed as oil-resistant).
In fact, UL 817 includes an additional test that must be passed in order to obtain special recognition for electrical cords that are specially designed to be oil-resistant. In this respect, the source of cautionary information that is affixed to the oil resistant insulation jacket must be able to withstand 48 hours of submersion in a fuel oil (e.g., diesel oil or the like) prior to being subjected to the 5 pound test, in order to obtain special recognition under UL 817 for application with oil-resistant cords. To date, it is believed that no affordable or marketable adhesive label has been able to satisfy UL 817 with respect to the fuel oil submersion test.
As an alternative to adhesive labels, another approach for providing a long-term source of cautionary information to electrical cords has involved the use of hang tags. A hang tag is commonly known in the art as a non-adhesive information or graphics source that is suspended on an item to be marked (e.g., an electrical cord) by way of a securement strap, such as, for example, a cable tie, or other form of physical attachment, as opposed to a tag that is sewn onto or inserted into the item to be marked. However, a significant drawback with using hang tags is that they previously have been limited to manual application with respect to electrical cords. Manually applying hang tags to electrical cords is cumbersome and results in increased labor costs and increased production time. Moreover, the Occupational Safety and Health Administration (OSHA) has strict guidelines relating to a minimal wrist movement for operators. Manual application of the hang tags with securement straps requires more wrist movement than OSHA permits.
Previous attempts to automatically apply the hang tags to the electrical cords have not met with success. For example, it has proven difficult to provide a hang tag that can be automatically applied and which also retains sufficient structural integrity to withstand long term "wear and tear" (e.g., to pass UL 817 Standard for cord sets and power supply cords, including those requiring oil resistance).
From the foregoing, it will be appreciated that there exists a need in the art for a method and apparatus for automatically applying a hang tag to an elongated object. It will also be appreciated that there exists a need for a hang tag for elongated objects which can be readily applied automatically, while at the same time, is able to withstand exposure to rigorous environmental conditions, as particularly encountered during use with electrical cords. It is an object of the present invention to provide such a method, apparatus, and hang tag that satisfies these needs. These and other objects and advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.